Disorders of eating are a significant problem in human mental health. Moreover, obtaining energy is one of the problems which all animals have to solve and engages neural mechanisms of broad general interest to Neuroscience. For these reasons, we have chosen to examine the roles played in the neural control of feeding by afferent, efferent and internuncial structures at various levels of the brain. An integrated program of research is proposed utilizing rat and pigeon as model systems for the study of sensorimotor and motivational control of the jaw in ingestive behavior, The topography of ingestive responses are described and quantified using a variety of movement transduction techniques; computer analysis of these data are used to clarify kinematic mechanisms underlying the movements. Anatomical tracing techniques (histochemistry, autoradiography, immunohistochemistry) serve to define ascending and descending pathways, identify motor and premotor structures and delineate connections between sensory and motor components of putative "ingestive" circuits. The contribution of circuit components to ingestive behavior is assessed using lesion techniques and behavioral assays, Correlations among jaw muscle activity and jaw movements are analyzed at the level of the muscle (EMG recording) and the motor and premotor neurons (extracellular unit recording). The physiological studies serve to link the anatomy to the behavior.